The present invention relates to an optical pickup driving apparatus for conveying an optical pickup for recording and reproducing in the diameter direction of a rotating optical disk so as to perform information seeking in an optical disk drive and particularly to an optical pickup driving apparatus with improved speed information seek operation.
With the development of the information industry, demand for processing information at higher speeds has been growing. In a compact disk player or magnetooptical disk drive, an optical disk is rotated by a spindle motor, and an optical pickup for recording and reproducing moves along a radius of the rotating disk so as to search for information thereon (called a coarse seek). In this structure, moving the whole optical pickup is unfavorable to high-speed seeking because of the burden of the feeding mechanism.
A conventional optical pickup, which is shown in FIG. 1, has a fixed portion 1 and a moving portion 2. To reduce the load of such an optical pickup, only moving portion 2 is mounted on a carriage 4 of a voice coil motor 3 which is a feeding mechanism. Moving portion 2 of the optical pickup essentially includes an actuator 8 for fine seek which minutely drives an objective lens 6 in the vertical and horizontal directions so that a beam spot converged by objective lens 6 precisely traces an accessed target track on a disk. The objective lens 6 for converges a light beam on optical disk 5 and a reflecting prism 7 for reflecting an incident beam and a reflected beam. However, since actuator 8 for fine seeking is composed of a plurality of coils, a permanent magnet and a yoke member, the actuator constitutes about half the overall weight of moving portion 2 and carriage 4. This greatly increases the load of voice coil motor 3. Accordingly, there is an upper limit to the speed of the seek operation in the conventional optical pickup driving apparatus.